Cooling apparatus



AP 1943. F. o. TRUMP 2,315,829

, COOLING APPARATUS Filed March 11, 1942 2 Sheets-Sheet l FREDERICK QTRUM INVENTOR ORNEYS v April 6, 1943. F. o. TRUMP 000mm APPARATUS Filed March 11, 1942 2 Sheets-Sheet 2 P M U R T O K C .R E D E R F R 0 T N E V m Patented Apr. 6, 1943 2,315,829 COOLING APPARATUS Frederick 0. Trump, Binghamton, N. Y., assignor to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware Application March 11, 1942, Serial No. 434,209

Claims.

The present invention relates to printing appa-= ratus for light-sensitive reproduction media, more particularly to an improved means for cooling the area around the source of light of the printing unit in such a printing apparatus.

It has been found that, in an apparatus of this type, particularly those wherein the printing unit consists of one or more inner stationary high pressure mercury vapor discharge units as the light source and an outer revolving glass cylinder as the printing surface in close proximity with the light source, a cooling system is necessary as otherwise an overabundance of heat collects from the light source. This causes the revolvable glass cylinder to become excessively heated so that the light-sensitive work piece, as it travels around the glass cylinder, becomes wrinkled and damaged. Enlarging the diameter of the revolvable' glass cylinder to increase its distance from the burner diminishes the printing speed and efilciency. As a result, several different cooling systems have been attempted, all of which were found to be unsatisfactory in one way or another.

One method is to place at one end of the printer unit a suction fan .to withdraw the hot air from the space between the burner and glass cylinder. However, removal of the air in such a manner leads to uneven temperatures in different sections of the revolving glass cylinder which, in turn, cause uneven printing. Blowing cool air into the area between the burner and glass cylinder from one end is objectionabl for the same reasons. Cool air has been blown against the'outside surface of the glass-cylinder but this requires large amounts of air since it is the conveyor belts encircling the glass cylinder which are directly cooled and the glass cylinder is only indirectly cooled. Alternating air flow mechanism, forcing cool air first from one end of the printer unit and then from the other, is very intricate and unwieldy.

'l'he object of this invention is, therefore, to provide a relatively simple inexpensive device which will remove excess heat and maintain a uniform temperature throughout the surface of the glass cylinder to insure even printing and maximum use of light intensity.

With this and other objects in mind, I have provided a cooling duct through the center of which the hot air, generated by light rays passing through the glass envelope surrounding the light source, is removed and cool air is drawn in from the ends into the space between the light source and glass cylinder.

The construction and arrangement of the parts which cooperate to accomplish the objects of the invention will be understood more readily from a consideration of the following-detailed description taken in connection with the accompanying drawings forming part of this specification. It is to be understood, however, that the invention is not confined to any strict conformity with the showing of the drawings which are for the purpose of illustrative disclosure and contemplate various changes in practice within the scope of the claims appended to this specification.

Referring now to the drawings:

F18. 1 is a perspective view, partly in section, of a burner, glass envelope, cooling duct and outer glass cylinder.

,Fig. 2 is a perspective view of the center section of the cooling duct showing the positioning of the hot air vents.

Fig. 3 is a plan view of the cooling duct.

Fig. 4 is an end view of the cooling duct.

Fig. 5 is a sectional end view of the burner assembly, the glass envelope, cooling duct and the outer glass cylinder partly in section.

In the drawings:

The printing or exposure area of the apparatus consists of an outer revolvable glass cylinder I of relatively small diameter; an inner stationary glass cylinder 2 of still smaller diameter, and a single mercury vapor discharge tube 3 within the stationary glass cylinder. The mercury discharge tube and'the two glass cylinders which surround it may be of any desired length, depending upon the type of Work to he handled by the machine. Although I prefer to use the inner stationary glass cylinder surrounding the light source 8, nevertheless that element may be dispensed with. I also prefer to use a high pressure quartz mercury vapor discharge tube as the light source unit but 7 flanges [3. The cooling duct 4 has a rectangular shaped bottom 5 and two angularly disposed sides or wing-like members 6 and 1 to facilitate placin: it inside the curved surface of glass cylinder 9. In the geometric center of box 4 are three vents, or intake 0 8, 9 and i0. through which hot air, generated by the passage of actinic rays through the glass envelope 2, may be withdrawn from the area surrounding the light source. Intake openings 8 and 9 are rectangular in shape and are located in the top edges of the duct sides and 1, while intake opening I. is circular in shape and is placed in the bottom 5. As hot air is drawn into intake openings l, 9 and Ill, it moves toward both ends of box 4 where exhaust outlets II and I! are attached to any suitable suction means (not shown in the drawings) and through which the hot air is discharged. The total area of exhaust outlets H and I2 is approximately equal to the total area of intake openings 8, 9

Y and I0. Removal of hot air by suction, allows cool air to be drawn simultaneously .from each end of revolvable glass cylinder l into the space around the light source to cool the revolvable glass cylinder and maintain a uniform temperature throughout the printing surface.

While I have described my invention with particularly reference to a preferred embodiment, it is understood that many Variants will suggest themselves to those skilled in the art as to the shape of the intake openings into the cooling duct and to the'shape of the duct itself without departing from the spirit or scope of this invention. It is not intended that my invention be limited to the construction herein described.

I claim: 7

i. In an apparatus for printing light-sensitive material having a transparent printing surface and a light source, a hollow box having angularly disposed sides, a plurality of intake openings in the geometric center of the surfaces of said box, and exhaust openings adapted for attachment to suitable suction means, the total area of said exhaust openings being approximately equal to the total area of the intake openings.

2. In an apparatus for printing light-sensitive material having a transparent cylindrical printing surface and a light source, a hollow rectangular box having two angularly disposed sides, said sides having intake openings in the center of the edges thereof, an intake opening in the geometric center of the bottom surface of said hollow box, and exhaust openings ateach end of the box for attachment to suitable suction means, the total area of said exhaust openings being approximately equal to the total area of the intake openinls.

3. In an apparatus for printing light-sensitive material having a transparent revolving cylindrical printing surface and a high pressure quartz'mercury vapor discharge tube, a hollow rectangular box having two angularly disposed sides, said sides having intake openings in the center of the edges thereof, an intake opening in the geometric center of the bottom surface of said hollow box, and exhaust openings at each end of the box for attachment to suitable suction means. the total area of said exhaust openings being approximately equal to the total area of the intake openings.

- 4. In an apparatus for printing light-sensitive material having a transparent revolving cylindrical printing surface and a high pressure high ultra-violet transmitting glass-mercury vapor discharge tube, a hollow rectangular box having two angularly disposed sides, said sides having intake openings in the center of-the edges thereof, an intake opening in the geometric center of the bottom surface of said hollow box, and exhaust openings at each end of the box for attachment to suitable suction means, the total area of said exhaust openings being approximately equal to the total area of the intake openings.

5. In an apparatus for printing light-sensitive material having a transparent cylindrical printing surface and a light source, a hollow rectangular box having two angularly disposed sides. said sides having rectangular intake openings in the center of the edges thereof, a circular intake opening in the geometric center of the bottom surface of said hollow box, and circular exhaust openings at each end of the box for attachment to suitable suction means, the total area of said exhaust openings being approximately equal to the total area of the intake openings.

FREDERICK O. TRUMP. 

